CN103513300A

CN103513300A - Light diffusion film

Info

Publication number: CN103513300A
Application number: CN201310176678.0A
Authority: CN
Inventors: 大类知生; 草间健太郎; 富冈健太; 片桐麦
Original assignee: Lintec Corp
Current assignee: Lintec Corp
Priority date: 2012-06-15
Filing date: 2013-05-14
Publication date: 2014-01-15
Anticipated expiration: 2033-05-14
Also published as: TWI606273B; JP6126802B2; KR20130141364A; KR102000511B1; TW201350927A; JP2014002187A; CN103513300B

Abstract

The invention provides a light diffusion film which can spread diffusion area of incident light and allows incident light diffusing not only along the longitudinal direction but also along the crossing direction at right angles to the longitudinal direction. Thus, the present invention relates to a light diffusion film having a long length shape or the like, composed by a first louver structure and a second louver structure in the order from a lower position, wherein each louver structure is composed of the multiple plate regions having different reflective indices and being formed by alternately arranging to an optional direction along the film surface, and wherein an acute angle [theta] 1 is set to be a value within a range of 10 to 90 DEG, which is observed from above of the film and which is an angle between the long axis direction of the plate of the first louver structure and the long axis direction of the plate of the second louver structure.

Description

Optical diffusion film

Technical field

The present invention relates to optical diffusion film.

The present invention be more particularly directed to by making incident light not only to the direction along its length direction, also carry out light diffusion and effectively expanded the optical diffusion film of the diffusion area of incident light to the direction with its length direction quadrature.

Background technology

In the past, for example, in the optical technical field under liquid crystal indicator etc., proposed to make incident light from specific direction to specific direction diffusion, to make from directly the keep straight on use of optical diffusion film of transmission of the incident light of the direction beyond this specific direction.

As such optical diffusion film, known have a variety of way, particularly, there is the optical diffusion film that the different a plurality of plate like region of refractive index are alternately configured to the shutter forming along the either direction along face and be widely used (for example, patent documentation 1～2).

That is, disclosing a kind of Opital control board (optical diffusion film) in patent documentation 1, it is characterized in that, is a kind of plastic sheet, to this sheet incident light of the above angular ranges of 2 of scatterings optionally.

In addition, the manufacture method of a kind of Opital control board (optical diffusion film) is disclosed in patent documentation 1, it is characterized in that being formed by following the 1st operation and the 2nd operation: the 1st operation, the resin combination that exists the compound in molecule with more than one polymerism carbon-to-carbon double bond of difference to form by a plurality of each refractive indexes is maintained in membranaceous, from specific direction irradiation ultraviolet radiation, makes said composition solidify; The 2nd operation is maintained in resin combination membranaceously on the solidfied material obtaining, and from the direction irradiation ultraviolet radiation different from the 1st operation, makes it solidify, and repeats as required the 2nd operation.

In addition, a kind of screen for projection is disclosed in patent documentation 2, it is characterized in that several the light control films (optical diffusion film) to be laminated, described light control film (optical diffusion film) has dependence of angle aspect mist degree, and make light with the angle of 0～180 ° during to its surperficial incident, the light scattering angle domain (light diffusion incident angle region) that shows more than 60% mist degree is more than 30 °, wherein, as shown in Figure 24 (a)～(b), in several light control films (optical diffusion film) 2 be with the direction of light scattering angle domain (light diffusion incident angle region) almost the mode of quadrature be laminated.

Patent documentation 1: Japanese kokai publication sho 63-309902 communique (claims)

Patent documentation 2: TOHKEMY 2005-316354 communique (claims)

Summary of the invention

Yet, in patent documentation 1, continuously a large amount of while producing optical diffusion film, on one side the coating layer that formed with composition by optical diffusion film with movements such as conveyors, use linear light source to irradiate active energy ray to this coating layer on one side, thereby manufacture the optical diffusion film of the shutter with regulation.

And then, for patent documentation 1, found following problem: although can access make incident light at the moving direction along coating layer, be the optical diffusion film that the direction of the length direction of film is carried out light diffusion, cannot obtain the optical diffusion film that makes incident light carry out light diffusion in the direction of the length direction quadrature with film.

More specifically, for the optical diffusion film that obtains making incident light carry out light diffusion in the direction of the length direction quadrature with film, need to form the shutter being formed by the plate like region of extending on the length direction of film.

Therefore,, in patent documentation 1, if form such shutter, linear light source is become along the mode of the direction of coating layer moving direction and is configured with the long axis direction of linear light source.

But, even if configure like this linear light source, while seeing due to the moving direction cross section from coating layer, each position at the Width of painting layer surface is different, cause active energy ray from linear light source with different angular illumination, so that the light diffusion property of the optical diffusion film obtaining also can become is inhomogeneous.

Therefore, in patent documentation 1, if obtain making incident light to carry out the strip optical diffusion film of light diffusion in the direction with its length direction quadrature, while being first necessary to obtain seeing film from above, there is the optical diffusion film of the shutter forming along Width configuration plate like region.Then, produce their severings and change 90 ° of directions and necessity that a plurality of optical diffusion films are engaged.Therefore, found in the seam portion light diffusing problem that inhomogeneous or film strength becomes and easily reduce and so on that becomes.

In addition, in patent documentation 1, essence is disclosed, and the bearing of trend of the plate like region in the shutter obtaining in the 1st operation is substantially parallel on the Width of film with the bearing of trend of plate like region in the shutter obtaining in the 2nd operation.

Therefore, found following problem: although make incident light carry out light diffusion to the direction along its length direction, may also to the direction with its length direction quadrature, not carry out light diffusion.

On the other hand, in patent documentation 2, as shown in Figure 24 (a)～(b), almost the mode of quadrature is stacked to make in multiple optical diffusion films 2 directions with light diffusion incident angle region, so at first sight, also can think and can make incident light not only in the direction along its length direction, also carry out light diffusion in the direction with its length direction quadrature.

Yet, for patent documentation 2, when producing optical diffusion film in a large number continuously, on one side the coating layer that also will utilize the movements such as conveyor to be formed with composition by optical diffusion film, Yi Bian use linear light source to irradiate active energy ray.

Therefore,, for the reason identical with patent documentation 1, the incident light that makes that is difficult to obtain as shown in Figure 24 (a) carries out the optical diffusion film 221 of light diffusion in the direction of the length direction quadrature with film.

Therefore, result is, even disclosed optical diffusion film in patent documentation 2, if the incident light that makes obtaining as shown in Figure 24 (a) carries out the strip optical diffusion film 221 of light diffusion in the direction with its length direction quadrature, also produce necessity that a plurality of optical diffusion films are engaged, so with patent documentation 1 similarly, in become inhomogeneous or film strength of seam portion light diffusing, become and easily reduce.

Therefore, found following problem: cannot by make incident light not only in the direction along its length direction, also in the direction with its length direction quadrature, carry out light and spread the diffusion area that effectively expands incident light.

In this case, the strip optical diffusion film of seeking to be easily applied to large picture screen etc. and not producing the problems such as seam.

That is, seek by making incident light not only in the direction along its length direction, also carry out light diffusion and effectively expand the strip optical diffusion film of the diffusion area of incident light in the direction with its length direction quadrature.

Therefore, the present inventor etc. are in view of as above situation and through going deep into effort, find the manufacture method of stipulating by enforcement, thereby can access the strip optical diffusion film that the bearing of trend of the plate like region in the 1st shutter and the bearing of trend of the plate like region in the 2nd shutter are formed with the angular cross of stipulating, thereby complete the present invention.

; the object of the present invention is to provide a kind of optical diffusion film; this optical diffusion film is by having the shutter of regulation; thereby make incident light not only to the direction along its length direction, also carry out light diffusion to the direction with its length direction quadrature, effectively expanded thus the diffusion area of incident light.

According to the present invention, a kind of optical diffusion film can be provided, and address the above problem, above-mentioned optical diffusion film is characterised in that, it is film thickness direction along film starts to have successively the strip of the 1st shutter and the 2nd shutter optical diffusion film from below, the 1st shutter and the 2nd shutter be by refractive index respectively different a plurality of plate like region form, and the different a plurality of plate like region of refractive index are at the shutter that alternately configured in parallel forms of the either direction along face, and, while seeing from film top, the acute angle theta 1 that the bearing of trend of the plate like region in the 1st shutter is become with the bearing of trend of plate like region in the 2nd shutter is the value in the scope of 10～90 °.

; if optical diffusion film of the present invention; that the bearing of trend of the plate like region in the 1st shutter and the bearing of trend of the plate like region in the 2nd shutter are formed with the angular cross of regulation, so can be by making incident light not only to the direction along its length direction, also carry out light diffusion and effectively expand the diffusion area of incident light to the direction with its length direction quadrature.

In addition, while forming optical diffusion film of the present invention, while preferably seeing from film top, the acute angle theta 2 that the bearing of trend of plate like region in the 1st shutter and the length direction of film are become is the value in the scope of 10～80 °, and while seeing from film top, the acute angle theta 3 that the bearing of trend of plate like region in the 2nd shutter and the length direction of film are become is the value in the scope of 10～80 °.

By such formation, thereby can effectively expand the diffusion area of incident light.

In addition, while forming optical diffusion film of the present invention, while preferably seeing from film top, the bearing of trend of the plate like region in the bearing of trend of the plate like region in the 1st shutter and the 2nd shutter is that line is symmetrical with respect to the imaginary line of the length direction quadrature with film.

By such formation, thereby can make incident light carry out more equably light diffusion.

In addition, while forming optical diffusion film of the present invention, preferably make the value in scope that the length on the Width of optical diffusion film is 0.1～3m, and to make the length on length direction be value more than 3m.

By such formation, thereby can access strip and the large-area optical diffusion film of the diffusion area that has effectively expanded incident light.

In addition, while forming optical diffusion film of the present invention, be preferably wound into that roller shape forms.

By such formation, thereby can access strip and the more large-area optical diffusion film of the diffusion area that has effectively expanded incident light.

In addition, while forming optical diffusion film of the present invention, preferably make the thickness of the 1st shutter and the 2nd shutter be respectively the value in the scope of 50～500 μ m.

By such formation, thereby can further effectively expand the diffusion area of incident light.

In addition, while forming optical diffusion film of the present invention, preferably make the width of the plate like region in the 1st shutter and the 2nd shutter be respectively the value in the scope of 0.1～15 μ m.

By such formation, can further effectively expand the diffusion area of incident light.

In addition, while forming optical diffusion film of the present invention, the starting material that preferably make diffusion barrier are the optical diffusion film composition that contains 2 kinds of polymerizable compounds that refractive index is different.

Accompanying drawing explanation

Fig. 1: Fig. 1 (a)～(b) is the figure providing for the summary of the shutter in optical diffusion film is described.

Fig. 2: Fig. 2 (a)～(b) is the figure providing for incident angle dependence, anisotropy and the angular aperture in optical diffusion film is described.

Fig. 3: Fig. 3 (a)～(c) is the figure providing for the basic comprising of optical diffusion film of the present invention is described.

Fig. 4: Fig. 4 (a)～(b) is the figure providing for shutter is described.

Fig. 5: Fig. 5 (a)～(c) is the figure providing for the bearing of trend of plate like region is described.

Fig. 6: Fig. 6 (a)～(b) is the figure providing for the shape of strip optical diffusion film is described.

Fig. 7: Fig. 7 (a)～(e) is the figure providing for the relation of the diffusion area of the bearing of trend of plate like region and incident light is described.

Fig. 8: Fig. 8 (a)～(e) is the photo providing for the relation of the diffusion area of the bearing of trend of plate like region and incident light is described.

Fig. 9: Fig. 9 (a)～(d) is the figure for each operation in the manufacture method of optical diffusion film of the present invention being described and providing.

Figure 10: Figure 10 (a)～(b) is for to having used the active energy ray of linear light source that the figure that describes and provide is provided.

Figure 11: Figure 11 (a)～(b) is the figure providing for the arrangement angles of linear light source is described.

Figure 12: Figure 12 is another figure in order to provide having used the active energy ray irradiation of linear light source to describe.

Figure 13: Figure 13 is for the formation of strip optical diffusion film of embodiment 1 being described and the figure that provides.

Figure 14: Figure 14 (a)～(b) is for the situation in cross section of strip optical diffusion film of embodiment 1 being described and the photo that provides.

Figure 15: Figure 15 (a)～(b) is for the light diffusion property of strip optical diffusion film of embodiment 1 being described and the figure that provides.

Figure 16: Figure 16 (a)～(c) is the figure providing for the formation of the 1st coating layer that is formed with the 1st shutter in description references example 1.

Figure 17: Figure 17 is the figure providing for the formation of the strip optical diffusion film of description references example 1.

Figure 18: Figure 18 (a)～(b) is for the situation in the cross section of the strip optical diffusion film of description references example 1 and the figure providing.

Figure 19: Figure 19 (a)～(b) is for the light diffusion property of the non-seam portion of the strip optical diffusion film of description references example 1 and the spectrogram and the photo that provide.

Figure 20: Figure 20 (a)～(b) is for the light diffusion property of the seam portion of the strip optical diffusion film of description references example 1 and the spectrogram and the photo that provide.

Figure 21: Figure 21 is for the formation of strip optical diffusion film of comparative example 1 being described and the figure that provides.

Figure 22: Figure 22 (a)～(b) is for the situation in cross section of strip optical diffusion film of comparative example 1 being described and the photo that provides.

Figure 23: Figure 23 (a)～(b) is for the light diffusion property of strip optical diffusion film of comparative example 1 being described and the spectrogram and the photo that provide.

Figure 24: Figure 24 (a)～(b) is the figure providing for the optical diffusion film in the past describes.

Embodiment

Embodiments of the present invention are a kind of optical diffusion films, it is characterized in that, along the film thickness direction of film, from below, to start to have successively the strip optical diffusion film of the 1st shutter and the 2nd shutter, the 1st shutter and the 2nd shutter be by refractive index respectively different a plurality of plate like region form, and the different a plurality of plate like region of refractive index are at the shutter that alternately configured in parallel forms of the either direction along face, and, while seeing from film top, the acute angle theta 1 that the bearing of trend of the plate like region in the 1st shutter is become with the bearing of trend of plate like region in the 2nd shutter is the value in the scope of 10～90 °.

Below, suitably with reference to accompanying drawing, illustrate embodiments of the present invention, but for this explanation is easily understood, first, for the ultimate principle of the light diffusion of optical diffusion film and the basic comprising of optical diffusion film of the present invention, describe.

1. the ultimate principle that the light in optical diffusion film spreads

At first, use the ultimate principle of the light diffusion of Fig. 1～2 pair optical diffusion film to describe.

First, Fig. 1 (a) represents the vertical view (planimetric map) of optical diffusion film 10, represents the optical diffusion film 10 shown in Fig. 1 (a) to cut off in the vertical direction along dotted line A-A the sectional view of the optical diffusion film 10 while seeing section from the direction of arrow in Fig. 1 (b).

In addition, Fig. 2 (a) represents the overall diagram of the optical diffusion film 10 is formed by 1 layer of shutter, and in Fig. 2 (b), expression is from directions X 2(a with the aid of pictures) optical diffusion film 10 time sectional view.

As shown in the planimetric map of this Fig. 1 (a), optical diffusion film 10 possesses in the either direction along face, plate like region 12 low plate like region 14 relative to the refractive index shutter 13 that alternately configured in parallel forms that refractive index is relatively high.

In addition, as shown in the sectional view of Fig. 1 (b), the plate like region 12 of high index of refraction and the plate like region 14 of relative low-refraction have respectively specific thickness relatively, in the normal direction (film thickness direction) of optical diffusion film 10, also keep the alternately state of configured in parallel.

Thus, as shown in Figure 2 (a) shows, incident angle is in light diffusion incident angle region time, infers incident light and is spread by optical diffusion film 10.

; as shown in Fig. 1 (b); incident light to the incident angle of optical diffusion film 10 with respect to the boundary surface 13 of shutter 13 ' be the value of the angular range from parallel to regulation; in other words; while spreading the value in incident angle region for light, infer the inside of the plate like region 12 of the relative high index of refraction of incident light (52,54) in shutter, Yi Bian change direction; along film thickness direction, pass on one side, thereby dissimilate at the direct of travel of the light of exiting surface side.

Its result, incident angle is in light diffusion incident angle region time, infers incident light by optical diffusion film 10 diffusions (52 ', 54 ').

On the other hand, when incident light is outer in light diffusion incident angle region to the incident angle of optical diffusion film 10, as shown in Fig. 1 (b), incident light 56 is not spread by optical diffusion film, and directly through optical diffusion film 10(56 ').

Should illustrate, in the present invention, " light diffusion incident angle region " refer to, with respect to optical diffusion film, and while changing the angle from the incident light of pointolite, the angular range of the incident light corresponding with the diffusion light of sending.

In addition, above-mentioned " light diffusion incident angle region " refer to, as shown in Figure 2 (a) shows, and according to the refringence of the shutter in optical diffusion film, pitch angle etc. and the angular regions definite to each this optical diffusion film.

According to above ultimate principle, possess the optical diffusion film 10 of shutter 13 for example as shown in Figure 2 (a) shows, can in optical transmission and diffusion, bring into play incident angle dependence.

In addition, as shown in Fig. 1～Fig. 2, the optical diffusion film with single shutter 13 has " anisotropy " conventionally.

Herein, " anisotropy " refers in the present invention, as shown in Figure 2 (a) shows, while having the diffusion of incident light tunicle, the spread condition of this light in the face parallel from film of the ejaculation light being diffused (enlarged shape of diffusion light) is because of the different and different character of the direction in this face.

More specifically, as shown in Figure 2 (a) shows, the shutter extending with either direction along along face in the contained composition of incident light for vertical composition, can optionally there is the diffusion of light, on the other hand, for the shutter contained with incident light for parallel composition, be difficult to occur the diffusion of light, so realize anisotropic light diffusion.

Therefore, as shown in Figure 2 (a) shows, the enlarged shape with the diffusion light of anisotropic optical diffusion film is substantially elliptical shape.

In addition, as mentioned above, the composition that contributes to the incident light of light diffusion be mainly the shutter that extends with the either direction along along face towards vertical composition, so as shown in Fig. 2 (b), in the present invention, while mentioning " incidence angle θ 4 " of incident light, refer to the incident angle towards vertical composition of the shutter extending with the either direction along along face.In addition, now, incidence angle θ 4 refer to angle when the angle of the normal of the incident side with respect to optical diffusion film is made as to 0 ° (°).

In addition, in the present invention, " light diffusion angular regions " refers to, with respect to optical diffusion film, pointolite is fixed on to the angle that incident light spreads most, the angular range of the diffusion light obtaining under this state.

And then, in the present invention, " angular aperture of diffusion light " refers to the width of above-mentioned " light diffusion angular regions ", as shown in Fig. 2 (b), refers to the angular aperture θ 5 of the diffusion light when parallel direction X Kan Mo cross section of the shutter that extends from either direction with along along face.

In addition, as shown in Figure 2 (a) shows, with regard to optical diffusion film, when the incident angle of incident light is contained in light diffusion incident angle region, even if this incident angle is different, also can carry out almost identical light diffusion in exiting surface side.

Therefore, resulting optical diffusion film has the optically focused effect that makes light concentrate on assigned position.

Should illustrate, with regard to the incident direction of light variation of high-refractive-index regions 12 inside in shutter, except become as shown in Fig. 1 (b) pass through total reflection and linearly, change the situation of nyctitropic step-refraction index type zig-zag type, also can consider to become curved shape and change the situation of nyctitropic graded index type.

In addition, at Fig. 1 (a) with (b), for simplicity the relatively high plate like region 12 low plate like region 14 interface relative to refractive index of refractive index represented with straight line, but in fact, interface is slightly tortuous, and each plate like region forms the complicated refractive index distribution structure with branch, disappearance.

Its result, infers different optical characteristics distributions and improves light diffusing.

2. basic comprising

Then, use Fig. 3 to describe the basic comprising of optical diffusion film of the present invention.

That is, as shown in Figure 3 (c), the feature of optical diffusion film 20 of the present invention is, along the film thickness direction of film, from below, starts to have successively the 2nd shutter 13b shown in the 1st shutter 13a shown in Fig. 3 (a) and Fig. 3 (b).

And then, the bearing of trend of the plate like region in the 1st shutter 13a shown in Fig. 3 (a), and the bearing of trend of the plate like region in the 2nd shutter 13b shown in Fig. 3 (b) is different, when from film, direction is seen, intersects.

Therefore,, if to the light of film incident for example first optical diffusion film of the present invention 20 makes, as shown in Figure 3 (b), by the 2nd shutter 13b, carry out anisotropic light diffusion.

Then,, as shown in Fig. 3 (a), the diffusion light of having carried out anisotropic light diffusion by the 2nd shutter 13b, further by the 1st shutter 13a, is carried out to anisotropic light diffusion in the direction different from the 2nd shutter 13b.

Its result, as shown in Figure 3 (c), incide optical diffusion film 20 of the present invention the rectangular shape of light carry out light diffusion, thereby can effectively expand the diffusion area of incident light.

Should illustrate, above-mentioned " below " refers to while coating layer being set on technique sheet material, the side that coating layer approaches with technique sheet material on film thickness direction.Therefore, be to be convenient to illustrate term of the present invention, the above-below direction of optical diffusion film itself is not carried out to any restriction.

In addition, " diffusion area of incident light " refer to, as shown in Figure 3 (c), during the diffusion of incident light tunicle, the diffusion photodistributed area of the ejaculation light being diffused in the face parallel with film of predetermined distance from film.

Below, the related optical diffusion film of present embodiment is described in detail.

3. the 1st shutter

(1) refractive index

In the 1st shutter, preferably make the specific refractivity between plate like region that refractive index is different, that is, the refractive index of plate like region of high index of refraction and the specific refractivity of the plate like region of relative low-refraction are more than 0.01 value relatively.

This reason be due to, by making above-mentioned specific refractivity, be more than 0.01 value, thereby can make incident light stably reflection in the 1st shutter, further improve the incident angle dependence from the 1st shutter.

More specifically, if above-mentioned specific refractivity is to be less than 0.01 value, incident light becomes narrow in the angle domain of the 1st shutter inner total reflection, and incident angle dependence excessively reduces sometimes.

Therefore, more preferably making the specific refractivity between plate like region that refractive index in the 1st shutter is different is more than 0.05 value, more preferably more than 0.1 value.

Should illustrate, the specific refractivity of the refractive index in the tabular region of high index of refraction and low-refraction plate like region is more preferred more greatly, but from the selected viewpoint that can form the material of the 1st shutter, thinks that 0.3 left and right is the upper limit.

In addition, in the 1st shutter, the value in the scope that the refractive index of the plate like region that preferred index is relatively high is 1.5～1.7.

Its reason be due to, if the refractive index in the tabular region of high index of refraction is to be less than 1.5 value, become too small with the difference of low-refraction plate like region, be sometimes difficult to obtain desirable shutter.On the other hand, if the refractive index in the tabular region of high index of refraction is for surpassing 1.7 value, the excessive step-down of intermiscibility between the material substance in composition for optical diffusion film sometimes.

Therefore, the value in the scope that the refractive index that more preferably makes the tabular region of high index of refraction in the 1st shutter is 1.52～1.65, the more preferably value in 1.55～1.6 scope.

Should illustrate, the refractive index in the tabular region of high index of refraction for example can be measured according to JIS K0062.

In addition, in the 1st shutter, the value in the scope that the refractive index that preferably makes the plate like region that refractive index is relatively low is 1.4～1.5.

Its reason be due to, if the refractive index of above-mentioned low-refraction plate like region be less than 1.4 value, the rigidity of resulting optical diffusion film reduces sometimes.On the other hand, if the refractive index of above-mentioned low-refraction plate like region is for surpassing 1.5 value, too diminish with the specific refractivity in the tabular region of high index of refraction, be sometimes difficult to obtain desirable shutter.

Therefore, the value in the scope that the refractive index that more preferably makes the low-refraction plate like region in the 1st shutter is 1.42～1.48, the more preferably value in 1.44～1.46 scope.

Should illustrate, the refractive index of low-refraction plate like region for example can be measured according to JIS K0062.

(2) width

In addition, as shown in Figure 4 (a), in the 1st shutter 13a, preferably make the width (S1, S2) of the tabular region 12 of high index of refraction that refractive index is different and low-refraction plate like region 14 be respectively the value in the scope of 0.1～15 μ m.

Its reason be due to, by making the width of these plate like region, be the value in the scope of 0.1～15 μ m, thereby can make incident light more stably reflection in the 1st shutter, can more effectively improve the incident angle dependence from the 1st shutter.

That is, if the width of above-mentioned plate like region is the value that is less than 0.1 μ m, there is the incident angle regardless of incident light, be all difficult to the situation of display light diffusion.On the other hand, if above-mentioned width is for surpassing the value of 15 μ m, the light of keeping straight in the 1st shutter increases, and sometimes spreads uniformity of light variation.

Therefore,, in the 1st shutter, more preferably make the width of the plate like region that refractive index is different be respectively the value in the scope of 0.5～10 μ m, the more preferably value in the scope of 1～5 μ m.

Should illustrate, width, length that forms the plate like region of the 1st shutter etc. can be measured by utilizing optical digital microscope to carry out film cross-section.

(3) pitch angle

In addition, as shown in Figure 4 (a), preferably, in the 1st shutter, the tabular region 12 of a plurality of highs index of refraction that refractive index is different and a plurality of low-refraction plate like region 14 are with constant tiltangleθ a configured in parallel, to form respectively with respect to film thickness direction.

Its reason be due to, by making each tiltangleθ a of plate like region constant, thereby can make incident light more stably reflection in the 1st shutter, further improve the incident angle dependence from the 1st shutter.

Should illustrate, θ a refers to that the vertical face of the 1st shutter extending in the either direction along with respect to along face cuts off Shi cross section by film, the pitch angle of the plate like region when angle by with respect to film normal to a surface of measuring is made as 0 ° (°).

More specifically, as shown in Figure 4 (a), refer to the angle of narrow side in the normal of upper surface of the 1st shutter and the topmost angulation of plate like region.Should illustrate, as shown in Figure 4 (a), the plate like region of take tilts Shi pitch angle to the right as benchmark, and the plate like region Shi pitch angle that tilts is to the left labeled as negative.

In addition, as shown in Figure 4 (b), the plate like region (12,14) that also preferably the refractive index in the 1st shutter is different bends to below along the film thickness direction of film from top.

Its reason be due to, by making plate like region crooked, thereby can make the balance of reflection in the 1st shutter and transmission complicated, effectively expand the angular aperture of diffusion light.

Should illustrate, can think that so crooked shutter is that polymerization rate that the utilization ultraviolet ray on the thickness direction by making to film is carried out slows down and obtains.

Particularly, can, by the ultraviolet illumination that suppresses to send from linear light source, make filming under irradiated state move and form with low speed.

(4) thickness

In addition, preferably make the thickness of the 1st shutter, that is, it is the value in the scope of 50～500 μ m that the 1st shutter in the film normal to a surface direction shown in Fig. 4 (a)～(b) exists the length L 1 of part.

Its reason be due to, by making the thickness of the 1st shutter, it is the value in above-mentioned scope, thereby can stably guarantee along the length of the 1st shutter of film thickness direction, make incident light more stably reflection in the 1st shutter, further improve the homogeneity from the diffusion light intensity in the light diffusion angular regions of the 1st shutter.

; if the thickness L1 of above-mentioned the 1st shutter is the value that is less than 50 μ m; the curtailment of the 1st shutter, the incident light of keeping straight in the 1st shutter increases, and is sometimes difficult to obtain the homogeneity of the diffusion light intensity in light diffusion angular regions.On the other hand, if the thickness L1 of above-mentioned the 1st shutter is for surpassing the value of 500 μ m, while optical diffusion film being formed to the 1st shutter with composition irradiation active energy ray, the shutter forming due to the initial stage causes photopolymerisable direct of travel to spread, and is sometimes difficult to form desirable the 1st shutter.

Therefore, the thickness L1 that more preferably makes the 1st shutter is the value in the scope of 70～300 μ m, the more preferably value in the scope of 80～200 μ m.

(5) bearing of trend

In addition, as shown in Fig. 5 (a), while preferably seeing from film top, making acute angle theta 2 that the bearing of trend N1 of the plate like region (12,14) in the 1st shutter 13a becomes with the length direction E ' of film is the value in the scope of 10～80 °.

Its reason be due to, by making the bearing of trend of the plate like region in the 1st shutter, it is the value in above-mentioned scope, combine with the bearing of trend of plate like region in the 2nd shutter, thereby can, by making incident light not only to the direction along its length direction, also to the direction with its length direction quadrature, carry out light and spread the diffusion area that effectively expands incident light.

; if above-mentioned acute angle is to be less than the value of 10 °; although also depend on the bearing of trend of the plate like region in the 2nd shutter, the light diffusion property to the direction diffusion of the length direction along film excessively reduces conventionally, and the diffusion area of incident light excessively diminishes sometimes.On the other hand, if above-mentioned acute angle is for surpassing the value of 80 °, although also depend on the bearing of trend of the plate like region in the 2nd shutter, the light diffusion property to the direction diffusion of the length direction quadrature with film excessively reduces conventionally, and the diffusion area of incident light excessively diminishes sometimes.

Therefore, while more preferably seeing from film top, the acute angle that the bearing of trend of plate like region in the 1st shutter and the length direction of film are become is the value in the scope of 35～55 °, and the value in the scope of 40～50 ° more preferably is further preferably the value in the scope of 44～46 °.

4. the 2nd shutter

The formation of the 2nd shutter is substantially identical with the formation of the 1st shutter, so avoid repetition, only records following point.

That is,, as shown in Fig. 5 (b), while preferably seeing from film top, making acute angle theta 3 that the bearing of trend N2 of the plate like region (12,14) in the 2nd shutter 13b becomes with the length direction E ' of film is the value in the scope of 10～80 °.

Its reason be due to, by making the bearing of trend of the plate like region in the 2nd shutter, it is the value in above-mentioned scope, thereby combine with the bearing of trend of plate like region in the 1st shutter, make incident light not only to the direction along its length direction, also to the direction with its length direction quadrature, carry out light diffusion, can effectively expand thus the diffusion area of incident light.

Therefore, while more preferably seeing from film top, the acute angle that the bearing of trend of plate like region in the 2nd shutter and the length direction of film are become is the value in the scope of 35～55 °, and the value in the scope of 40～50 ° more preferably is further preferably the value in the scope of 44～46 °.

5. thickness

In addition, preferably making the thickness of optical diffusion film is the value in the scope of 50～500 μ m.

Its reason be due to, if above-mentioned thickness is the value that is less than 50 μ m, the length of the shutter of the film thickness direction forming in film excessively shortens, the incident light of keeping straight in shutter increases, and is sometimes difficult to obtain sufficient incident angle dependence.On the other hand, if above-mentioned thickness is for surpassing the value of 500 μ m, irradiation light for a long time, causes spreading so production excessively reduces or irradiate the shutter that light forms due to the initial stage, is sometimes difficult to form desirable shutter.

Therefore, the thickness that more preferably makes optical diffusion film is the value in the scope of 70～300 μ m, the more preferably value in the scope of 80～200 μ m.

Should illustrate, on the film thickness direction of optical diffusion film, for example, in skin section etc., also can have the non-existent part of shutter.

Therefore, the thickness of optical diffusion film equals the total of the thickness of the 1st shutter and the thickness of the 2nd shutter, or surpasses the total of the thickness of the 1st shutter and the thickness of the 2nd shutter.

6. the shape of film

In addition, the shape of optical diffusion film of the present invention is characterised in that it is strip.

More specifically, as shown in Figure 6 (a), preferably make the value in scope that the length L 2 on the Width (Width) of optical diffusion film 10 is 0.1～3m, more preferably the value in the scope of 0.5～2m.

On the other hand, the length for length direction, is not particularly limited.

That is, optical diffusion film of the present invention can be manufactured continuously by manufacture method described later.

Therefore, the length L 3 for length direction, is preferably value more than 3m, more preferably value more than 15m.

Its reason be due to, by making film form such shape, thereby can access, can make incident light not only to the direction along its length direction, the strip from light diffusion to the direction with its length direction quadrature and the large-area optical diffusion film that also carry out.

In addition, as shown in Figure 6 (b), preferred light diffusion barrier 20 is wound into roller shape.

Its reason be due to, by forming roller shape, thereby can access, can make incident light in the direction with its length direction quadrature or near the direction it, carry out strip and the more large-area optical diffusion film of light diffusion.

In addition, the operability in the time of can improving preservation, carrying.

That is, roller shape if, even when the size of the display of application film etc. is varied, also can after cut into the size that each needs.

In addition, roller shape,, in ensuing operation, can utilize roller to roller method (roll to roll) and other film laminating if, compares and can boost productivity to the situation of sheet method (sheet to sheet) with adopting sheet.

7. the combination of bearing of trend

In addition, in optical diffusion film of the present invention, as shown in Fig. 5 (c), while preferably seeing from film top, the acute angle theta 1 that the bearing of trend N1 of the plate like region (12,14) in the 1st shutter 13a is become with the bearing of trend N2 of plate like region (12,14) in the 2nd shutter 13b is the value in the scope of 10～90 °.

Its reason be due to, by such formation, thereby can access by making incident light not only to the direction along its length direction, also carry out light diffusion and effectively expanded the strip film of the diffusion area of incident light to the direction with its length direction quadrature.

That is,, if above-mentioned acute angle is to be less than the value of 10 °, the diffusion area of incident light excessively diminishes sometimes.

Therefore, while more preferably seeing from film top, the acute angle that the bearing of trend of the plate like region in the 1st shutter is become with the bearing of trend of plate like region in the 2nd shutter is the value in the scope of 80～90 °, the value in the scope of 85～90 ° more preferably, is further preferably the value in the scope of 89～90 °.

In addition, as shown in Fig. 5 (c), while preferably seeing from film top, the bearing of trend N2 of the bearing of trend N1 of the plate like region in the 1st shutter 13a (12,14) and the plate like region (12,14) in the 2nd shutter 13b is that line is symmetrical with respect to the imaginary line E ' ' of the length direction E ' quadrature with film.

Its reason is that the bearing of trend due to the plate like region in, the bearing of trend by making the plate like region in the 1st shutter and the 2nd shutter intersects like this, thereby can make incident light carry out more equably light diffusion.

; particularly; be θ 2=45 °, θ 3=45 °; or while being respectively near its value; by making the bearing of trend of the plate like region in each shutter, be that line is symmetrical; thereby shown in Fig. 7 (a), can respectively the expansion on the expansion on the left and right directions of diffusion light and above-below direction be expanded to greatest extent as described later.

Therefore, by above-mentioned optical diffusion film when the screen, can be respectively by horizontal field angle and longitudinally field angle expand to greatest extent.

Use Fig. 7 (a)～(e), the relation of the diffusion area of the bearing of trend of plate like region and incident light is described herein.

That is the spread condition 50′， right side that, Fig. 7 (a)～(e) represents respectively the 1st shutter 13a and incides its light in left side represent the 2nd shutter 13b and incide the spread condition 51 of its diffusion light of utilizing the 1st shutter 13a '.

First, the spread condition of incident light when Fig. 7 (a) represents 1=90 ° of θ, θ 2=45 °, θ 3=45 °, the diffusion area of known final incident light fully expands (51 ').

On the other hand, the spread condition of incident light when Fig. 7 (b) represents 1=60 ° of θ, θ 2=30 °, θ 3=30 °, compare with the situation of Fig. 7 (a), the light diffusion property of the known diffusion of the direction to the length direction E ' along film reduces, and the diffusion area of incident light diminishes (51 ').

In addition, the spread condition of incident light when Fig. 7 (c) represents 1=60 ° of θ, θ 2=60 °, θ 3=60 °, compare with the situation of Fig. 7 (a), the light diffusion property of the known diffusion of the direction to the length direction E ' quadrature with film reduces, and the diffusion area of incident light diminishes (51 ').

In addition, the spread condition of incident light when Fig. 7 (d) represents 1=30 ° of θ, θ 2=15 °, θ 3=15 °, compare with the situation of Fig. 7 (a), the light diffusion property of the known diffusion of the direction to the length direction E ' along film further reduces, and the diffusion area of incident light further diminishes (51 ').

In addition, the spread condition of incident light when Fig. 7 (e) represents 1=30 ° of θ, θ 2=75 °, θ 3=75 °, compare with the situation of Fig. 7 (a), the light diffusion property of the known diffusion of the direction to the length direction E ' quadrature with film further reduces, and the diffusion area of incident light further diminishes (51 ').

Should illustrate, will be shown in Fig. 8 (a)～(e) with the photo of corresponding diffusion light of Fig. 7 (a)～(e).

8. adhesive phase

In addition, utilize manufacture method of the present invention and the optical diffusion film that obtains possesses for clung body is carried out to stacked adhesive phase at its single or double.

Bonding agent as forming above-mentioned adhesive phase, is not particularly limited, and can use in the past the bonding agents such as known acrylic acid series, silicon-type, urethane system, rubber series.

9. manufacture method

In addition, optical diffusion film of the present invention for example can utilize the manufacture method manufacture that comprises following operation (a)～(e).

(a) operation of composition for the optical diffusion film that preparation contains 2 kinds of polymerizable compounds that refractive index is different;

(b), to technique sheet material coating optical diffusion film composition, form the operation of the 1st coating layer;

(c) for the 1st coating layer, Yi Bian the 1st coating layer is moved, Yi Bian use linear light source to carry out the 1st active energy ray, irradiate, form the operation of the 1st shutter;

(d) to being formed with the 1st coating layer of the 1st shutter, coating optical diffusion film composition, the operation of the duplexer that formation consists of the 1st coating layer and the 2nd coating layer;

(e) to the 2nd coating layer, the duplexer consisting of the 1st coating layer and the 2nd coating layer is moved on one side, using linear light source to carry out the 2nd active energy ray on one side irradiates, form the 2nd shutter, wherein, while seeing from film top, the operation of the value in the scope that the acute angle theta 1 that the long axis direction of the linear light source of the long axis direction of linear light source when the 1st active energy ray is irradiated during with the 2nd active energy ray irradiation becomes ' be is 10～90 °.

Below, with reference to accompanying drawing, above-mentioned manufacture method is specifically described.

(1) operation (a): the preparatory process of composition for optical diffusion film

Operation (a) is to prepare the operation of composition for the optical diffusion film of regulation.

More specifically, be preferably different at least 2 kinds of polymerizable compounds, the Photoepolymerizationinitiater initiater of refractive index and the operation of mixing according to other required and fixed adjuvant.

In addition, while mixing, can at room temperature directly stir, but from improving inhomogeneity viewpoint, for example, preferably under the heating condition of 40～80 ℃, stir, form uniform mixed liquor.

In addition, also preferably further add thinning agent to become the desirable viscosity that is applicable to application.

Below, operation (a) is carried out to more specific description.

(1)-1 high index of refraction polymerizable compound

(i) kind

In different 2 polymerizable compounds of refractive index, the kind of the polymerizable compound that refractive index is relatively high (following, to be sometimes referred to as (A) composition) is not particularly limited, but preferably make its major component, is (methyl) acrylate that contains a plurality of aromatic rings.

Its reason is as follows owing to inferring: as (A) composition, by containing specific (methyl) acrylate, thereby the polymerizable compound that the polymerization speed specific refractivity that can make (A) composition is relatively low is (following, be sometimes referred to as (B) composition) polymerization speed fast, make the polymerization speed between these compositions produce the poor of regulation, effectively reduce the copolymerizable of two compositions.

Its result, while carrying out photocuring, can efficiency form from the plate like region of (A) composition and the so-called shutter alternately extending from the plate like region of (B) composition well.

In addition, infer as (A) composition, by containing specific (methyl) acrylate, although thereby there is sufficient intermiscibility at monomer stage and (B) composition, but can be in polymerization process, in a plurality of connected stages, make to be reduced to the intermiscibility of (B) composition the scope of regulation, further efficiency forms shutter well.

And then, as (A) composition, by containing specific (methyl) acrylate, thereby improve the refractive index of the plate like region from (A) composition in shutter, the specific refractivity of the plate like region with from (B) composition is adjusted to the above value of regulation.

Therefore, as (A) composition, by containing specific (methyl) acrylate, combine with the characteristic of (B) described later composition, thereby can obtain efficiently the plate like region that refractive index is different, alternately extend the shutter forming.

Should illustrate, " (methyl) acrylate that contains a plurality of aromatic rings " refers to that the ester residue at (methyl) acrylate partly has the compound of a plurality of aromatic rings.

In addition, " (methyl) acrylic acid " refer to acrylic acid and methacrylic acid the two.

In addition, (methyl) acrylate that contains a plurality of aromatic rings as such conduct (A) composition, for example can enumerate (methyl) biphenyl acrylate, (methyl) acrylic acid naphthalene ester, (methyl) acrylic acid anthracene ester, (methyl) acrylic acid benzyl phenyl ester, (methyl) acrylic acid xenyl oxygen base Arrcostab, (methyl) acrylic acid naphthyl oxygen base Arrcostab, (methyl) acrylic acid anthryl oxygen base Arrcostab, (methyl) acrylic acid benzyl phenyl oxygen base Arrcostab etc., or a part for the hydrogen atom on aromatic rings is by halogen, alkyl, alkoxy, haloalkyl etc. replace and (methyl) acrylate etc.

In addition, (methyl) acrylate that contains a plurality of aromatic rings for as (A) composition, preferably comprises the compound that contains cyclohexyl biphenyl, particularly preferably comprises the biphenol compound being represented by following general formula (1).

(in general formula (1), R ¹～R ¹⁰independent separately, R ¹～R ¹⁰in at least one be the substituting group being represented by following general formula (2), all the other are any substituting group in hydrogen atom, hydroxyl, carboxyl, alkyl, alkoxy, haloalkyl, hydroxy alkyl, carboxyalkyl and halogen atom)

(in general formula (2), R ¹¹for hydrogen atom or methyl, the integer that carbon number n is 1～4, the integer that repeat number m is 1～10)

Its reason is as follows owing to inferring: as (A) composition, by containing the biphenol compound with ad hoc structure, thereby can make (A) composition and (B) polymerization speed of composition produce the poor of regulation, make (A) composition and (B) intermiscibility of composition be reduced to the scope of regulation, reduce the copolymerizable of twenty percent between dividing.

In addition, can improve the refractive index of the plate like region from (A) composition in shutter, more easily the specific refractivity of the plate like region with from (B) composition is adjusted to the above value of regulation.

In addition, the R in general formula (1) ¹～R ¹⁰while containing any in alkyl, alkoxy, haloalkyl, hydroxy alkyl and carboxyalkyl, the value in the scope that the carbon number that preferably makes its moieties is 1～4.

Its reason be due to, if above-mentioned carbon number is for surpassing 4 value, the polymerization speed of (A) composition reduces or becomes too low from the refractive index of the plate like region of (A) composition, is sometimes difficult to form efficiently shutter.

Therefore, the R in general formula (1) ¹～R ¹⁰while containing any in alkyl, alkoxy, haloalkyl, hydroxy alkyl and carboxyalkyl, the value in the scope that the carbon number that more preferably makes its moieties is 1～3, the more preferably value in 1～2 scope.

In addition, the R in preferred formula (1) ¹～R ¹⁰substituting group for beyond haloalkyl or halogen atom, does not contain the substituting group of halogen that is.

Its reason is owing to preventing producing two when burning optical diffusion film etc. english, from the viewpoint of environmental protection and preferably.

Should illustrate, in the optical diffusion film that possesses shutter in the past, while obtaining the shutter of regulation, for the object that makes monomer component high index of refraction, conventionally in monomer component, enter halogen and replace.

In this respect, if the biphenol compound being represented by general formula (1), even if do not carry out halogen replacement, also can form high refractive index.

Therefore, if even the optical diffusion film that the optical diffusion film in the present invention is formed with composition photocuring, while not containing halogen, also can be brought into play good incident angle dependence.

Should illustrate, " good incident angle dependence " refers to, light diffusion incident angle region is not diffused with incident light and the difference in the non-diffusion incident angle region of direct transmission is clearly controlled.

In addition, the R in general formula (1) ²～R ⁹in any be preferably the substituting group being represented by general formula (2).

Its reason be due to, by making the substituent position being represented by general formula (2), be R ¹and R ¹⁰position in addition, thus can effectively prevent that stage (A) composition before carrying out photocuring is orientated and crystallization each other.

And then the monomer stage before carrying out photocuring, for liquid, even if do not use diluting solvent etc., also can evenly be mixed with (B) composition on apparent.

Thus, in the stage of photocuring, (A) composition and (B) condensing, being separated in the trickle level of composition can be there is, the optical diffusion film of shutter can be obtained more efficiently possessing.

And then, from identical viewpoint, the R in general formula (1) particularly preferably ³, R ⁵, R ⁶and R ⁸in any be the substituting group that general formula (2) represents.

In addition, the integer that the substituent repeat number m that conventionally preferably makes general formula (2) represent is 1～10.

Its reason be due to, if repeat number m becomes the value that surpasses 10, the oxyalkylene chain that connects polymerization position and cyclohexyl biphenyl becomes long, sometimes hinders the polymerization between (A) composition in polymerization position.

Therefore, the integer that the substituent repeat number m that more preferably makes to be represented by general formula (2) is 1～4, is particularly preferably 1～2 integer.

Should illustrate, from identical viewpoint, the integer that the substituent carbon number n that conventionally preferably makes to be represented by general formula (2) is 1～4.

In addition, if also consider that, cyclohexyl biphenyl excessively near with respect to cyclohexyl biphenyl as the position of the polymerism carbon-to-carbon double bond at polymerization position becomes situation sterically hindered and that the polymerization speed of (A) composition is reduced, the integer that the substituent carbon number n that more preferably makes to be represented by general formula (2) is 2～4, is particularly preferably 2～3 integer.

In addition, as the concrete example of the biphenol compound being represented by general formula (1), can preferably enumerate the compound being represented by following formula (3)～(4).

(ii) molecular weight

In addition, the value in the scope that the molecular weight that preferably makes (A) composition is 200～2500.

Its reason is as follows owing to inferring: by the scope that makes the molecular weight of (A) composition be regulation, thereby can make the polymerization speed of (A) composition further accelerate, more effectively reduction (A) composition and (B) copolymerizable of composition.

Its result, while carrying out photocuring, can form more efficiently from the plate like region of (A) composition and alternately extend from the plate like region of (B) composition the shutter forming.

That is, if (A) molecular weight of composition is to be less than 200 value,, because the sterically hindered polymerization speed that causes reduces, becomes and approach with the polymerization speed of (B) composition, sometimes easily produce and (B) copolymerization of composition.On the other hand, if (A) molecular weight of composition is for surpassing 2500 value, the difference along with the molecular weight with (B) composition diminishes, (A) polymerization speed of composition reduces, become and approach with the polymerization speed of (B) composition, infer easy generation and (B) copolymerization of composition, its result, is sometimes difficult to efficiency and forms well shutter.

Therefore, the value in the scope that the molecular weight that more preferably makes (A) composition is 240～1500, the more preferably value in 260～1000 scope.

Should illustrate, with regard to the molecular weight of (A) composition, can, according to being tried to achieve by the forming of molecule, calculated value that the atomic weight of constituting atom obtains, also can use gel permeation chromatography (GPC) to measure weight-average molecular weight.

(iii) use separately

In addition, the optical diffusion film in the present invention is to contain (A) composition as the monomer component of the relatively high plate like region of the refractive index in formation shutter by the feature of composition, but preferably (A) composition contains with single composition.

Its reason be due to, by such formation, thereby can effectively suppress the plate like region from (A) composition, in other words, the fluctuation of the refractive index of the plate like region that refractive index is relatively high, obtains possessing the optical diffusion film of shutter more efficiently.

; (A) when composition is low with respect to the intermiscibility of (B) composition, for example, when (A) composition is halogen based compound etc.; sometimes and for example, with other (A) composition (, non-halogen based compound etc.) as being used for making (A) composition and the 3rd composition that (B) composition mixes.

Yet now, due to the impact of above-mentioned the 3rd composition, the refractive index from the relatively high plate like region of the refractive index of (A) composition produces fluctuation or easily reduces sometimes.

Its result, sometimes becomes inhomogeneous or easily excessively reduces with the refringence of the relative low plate like region of refractive index from (B) composition.

Therefore, preferably select to have the monomer component with the high index of refraction of the intermiscibility of (B) composition, and make to use it as independent (A) composition.

Should illustrate, for example, if as the biphenol compound being represented by formula (3) of (A) composition, owing to being low viscosity, so there is the intermiscibility with (B) composition, therefore can use as independent (A) composition.

(iv) refractive index

In addition, the value in the scope that the refractive index that preferably makes (A) composition is 1.5～1.65.

Its reason be due to, by making the refractive index of (A) composition, it is the value in above-mentioned scope, thereby can more easily regulate the specific refractivity with plate like region from (B) composition from the refractive index of the plate like region of (A) composition, obtain more efficiently possessing the optical diffusion film of shutter.

That is, if (A) refractive index of composition is to be less than 1.5 value, become too small with the specific refractivity of (B) composition, be sometimes difficult to obtain effective light diffusion angular regions.On the other hand, if (A) refractive index of composition is for surpassing 1.65 value, although become large with the specific refractivity of (B) composition, sometimes with (B) composition apparent on the state that mixes be also difficult to formation.

Therefore, the value in the scope that the refractive index that more preferably makes (A) composition is 1.52～1.65, the more preferably value in 1.56～1.6 scope.

Should illustrate, the refractive index of above-mentioned (A) composition refers to the refractive index of utilizing irradiation to be cured previous (A) composition.

In addition, refractive index for example can be measured according to JIS K0062.

(v) content

In addition, preferably making optical diffusion film is the value in the scope of 25～400 weight portions with (B) composition 100 weight portions of the content of (A) composition in the composition polymerizable compound relatively low with respect to refractive index described later.

Its reason be due to, if (A) content of composition is the value that is less than 25 weight portions, (A) composition tails off with respect to the ratio that exists of (B) composition, from the width of the plate like region of (A) composition, compare excessively and diminish with the width of plate like region from (B) composition, be sometimes difficult to obtain having the dependent shutter of good incident angle.In addition, the length of the window shutter of the thickness direction of optical diffusion film becomes insufficient, sometimes display light diffusivity not.On the other hand, if (A) content of composition is for surpassing the value of 400 weight portions, (A) composition becomes many with respect to the ratio that exists of (B) composition, from the width of the plate like region of (A) composition and the width of plate like region from (B) composition, compare excessive change large, be sometimes difficult on the contrary obtain having the dependent shutter of good incident angle.In addition, the length of the window shutter of the thickness direction of optical diffusion film becomes insufficient, sometimes display light diffusivity not.

Therefore, the content that more preferably makes (A) composition is the value in the scope of 40～300 weight portions, the more preferably value in the scope of 50～200 weight portions with respect to (B) composition 100 weight portions.

(1)-2 low-refraction polymerizable compounds

(i) kind

In the different 2 kinds of polymerizable compounds of refractive index; the kind of the polymerizable compound that refractive index is relatively low ((B) composition) is not particularly limited; as its major component; such as enumerating urethane (methyl) acrylate, there are (methyl) acrylic acid series polymeric compounds of (methyl) acryloyl group, the organic siliconresin that contains (methyl) acryloyl group, unsaturated polyester resin etc. at side chain, but be particularly preferably urethane (methyl) acrylate.

Its reason be due to, if urethane (methyl) acrylate, not only can more easily regulate the specific refractivity with plate like region from (B) composition from the refractive index of the plate like region of (A) composition, can also effectively suppress the fluctuation from the refractive index of the plate like region of (B) composition, obtain more efficiently possessing the optical diffusion film of shutter.

Therefore, below, mainly urethane (methyl) acrylate as (B) composition is described.

Should illustrate, (methyl) acrylate refer to acrylate and methacrylate the two.

First, urethane (methyl) acrylate by (B1) at least contain the compound, (B2) polyol compound of 2 isocyanate group and (B3) (methyl) acrylic acid hydroxyalkyl acrylate form, wherein, (B2) preferably diatomic alcohol compounds, particularly preferably poly alkylene glycol.

Should illustrate, (B) in composition, also contain the oligomer of the repetitive with urethane bond.

Wherein, as (B1) composition, at least contain the compound of 2 isocyanate group, for example can enumerate 2, 4-toluene diisocyanate, 2, 6-toluene diisocyanate, 1, 3-XDI, 1, the aromatic poly-isocyanates such as 4-XDI, the aliphatic polymeric isocyanates such as hexamethylene diisocyanate, isophorone diisocyanate (IPDI), the ester ring type polyisocyanates such as hydrogenated diphenyl methane diisocyanate, and their biuret body, isocyanuric acid ester body, and conduct and ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, the adduct of the reactant of the low molecule active hydrogen-contg compound of castor-oil plant wet goods (for example, XDI is three-functionality-degree adduct) etc.

In addition, above-mentioned in, be particularly preferably ester ring type polyisocyanate.

Its reason be due to, ester ring type polyisocyanate, compares with aliphatic polymeric isocyanate if, due to relations such as space conformations, easily the reaction velocity of each isocyanate group is arranged to difference.

Thus, can suppress (B1) composition and only react with (B2) composition, or (B1) composition only reacts with (B3) composition, can make (B1) composition and (B2) composition and (B3) composition react reliably, prevent the generation of unnecessary accessory substance.

Its result, can suppress the plate like region from (B) composition in shutter effectively, that is, and and the fluctuation of the refractive index of low-refraction plate like region.

In addition, ester ring type polyisocyanate, compares with aromatic poly-isocyanate if, (B) composition obtaining and (A) intermiscibility of composition can be reduced to the scope of regulation, forms more efficiently shutter.

And then, if ester ring type polyisocyanate, compare with aromatic poly-isocyanate, the refractive index of (B) composition that can reduce to obtain, so can increase the specific refractivity with (A) composition, display light diffusivity, and further efficiency more reliably forms the high shutter of diffusion uniformity of light in light diffusion angular regions well.

In addition, in such ester ring type polyisocyanate, preferably only contain the ester ring type diisocyanate of 2 isocyanate group.

Its reason be due to, if ester ring type diisocyanate, can react with (B3) component quantifying ground with (B2) composition, obtain single (B) composition.

As such ester ring type diisocyanate, can particularly preferably enumerate as isophorone diisocyanate (IPDI).

Its reason be due to, can effective difference be set to the reactivity of 2 isocyanate group.

In addition, in forming the composition of urethane (methyl) acrylate, as (B2) composition, be poly alkylene glycol, such as enumerating polyglycol, polypropylene glycol, polytetramethylene glycol, poly-hexanediol etc., wherein, be particularly preferably polypropylene glycol.

Its reason be due to, if polypropylene glycol, viscosity is low, so can carry out solvent-free processing.

In addition, if polypropylene glycol, while making (B) composition solidify, becomes the good soft chain segment in this solidfied material, can effectively improve the operability of optical diffusion film, installation property.

Should illustrate, (B) weight-average molecular weight of composition can be mainly weight-average molecular weight by (B2) composition regulate.Herein, (B2) weight-average molecular weight of composition is generally 2300～19500, is preferably 4300～14300, is particularly preferably 6300～12300.

In addition, in forming the composition of urethane (methyl) acrylate, as (B3) composition, be (methyl) acrylic acid hydroxyalkyl acrylate, such as enumerating (methyl) acrylic acid 2-hydroxy methacrylate, (methyl) acrylic acid 2-hydroxy propyl ester, (methyl) acrylic acid 3-hydroxy propyl ester, (methyl) acrylic acid 2-hydroxyl butyl ester, (methyl) acrylic acid 3-hydroxyl butyl ester, (methyl) acrylic acid 4-hydroxyl butyl ester etc.

In addition, from reducing the polymerization speed of resulting urethane (methyl) acrylate, the viewpoint that forms more efficiently the shutter of regulation is set out, particularly more preferably methacrylic acid hydroxyl Arrcostab, more preferably 2-hydroxyethyl methacrylate.

In addition, utilize the synthetic of urethane (methyl) acrylate that (B1)～(B3) composition carries out to implement according to conventional methods.

Now, preferably make (B1)～(B3) mixing ratio of composition be take molar ratio computing as (B1) composition: (B2) composition: (B3) ratio of composition=1～5:1:1～5.

Its reason be due to, by being above-mentioned mixing ratio, thereby can synthesize efficiently 2 hydroxyls that 1 isocyanate group that (B1) composition has has with (B2) composition, react and bonding respectively, and (B3) another isocyanates radical reaction that hydroxyl that composition has and 2 (B1) compositions have respectively and urethane (methyl) acrylate that bonding generates.

Therefore, more preferably make (B1)～(B3) mixing ratio of composition be take molar ratio computing as (B1) composition: (B2) composition: (B3) ratio of composition=1～3:1:1～3, the more preferably ratio of 2:1:2.

(ii) weight-average molecular weight

In addition, the value in the scope that the weight-average molecular weight that preferably makes (B) composition is 3000～20000.

Its reason is due to, the scope that the weight-average molecular weight by above making (B) composition is regulation, thus can make (A) composition and (B) polymerization speed of composition produce the poor of regulation, effectively reduce the copolymerizable of two compositions.

Its result, while carrying out photocuring, can efficiency form from the plate like region of (A) composition and alternately extend from the plate like region of (B) composition the shutter forming well.

; if (B) weight-average molecular weight of composition is to be less than 3000 value, the polymerization speed of (B) composition accelerates, and becomes and approaches with the polymerization speed of (A) composition; easily produce and (A) copolymerization of composition, result is sometimes difficult to efficiency and forms well shutter.On the other hand, if (B) weight-average molecular weight of composition is for surpassing 20000 value, be sometimes difficult to form from (A) composition and (B) plate like region of composition alternately extend the shutter forming or excessively reduce and (A) composition was separated out in the coating stage with the intermiscibility of (A) composition.

Therefore, the value in the scope that the weight-average molecular weight that more preferably makes (B) composition is 5000～15000, the more preferably value in 7000～13000 scope.

Should illustrate, (B) weight-average molecular weight of composition can be used gel permeation chromatography (GPC) to measure.

(iii) use separately

In addition, (B) composition can be used together different two or more of molecular structure, weight-average molecular weight, but from suppressing the viewpoint of fluctuation of the refractive index of the plate like region from (B) composition shutter, preferably only uses a kind.

; while using a plurality of (B) composition; from the refractive index of the relatively low plate like region of the refractive index of (B) composition, produce fluctuation or uprise, sometimes become inhomogeneous or excessively reduce with the refringence of the relative high plate like region of refractive index from (A) composition.

(iv) refractive index

In addition, the value in the scope that the refractive index that preferably makes (B) composition is 1.4～1.55.

Its reason be due to, by making the refractive index of (B) composition, it is the value in above-mentioned scope, thereby can more easily regulate the specific refractivity with plate like region from (B) composition from the plate like region of (A) composition, manufacture more efficiently the optical diffusion film that possesses shutter.

That is,, if (B) refractive index of composition is to be less than 1.4 value, although become large with the specific refractivity of (A) composition, the intermiscibility extreme variation with (A) composition, likely cannot form shutter.On the other hand, if (B) refractive index of composition, for surpassing 1.55 value, becomes too small with the specific refractivity of (A) composition, be sometimes difficult to obtain desirable incident angle dependence.

Therefore, the value in the scope that the refractive index that more preferably makes (B) composition is 1.45～1.54, the more preferably value in 1.46～1.52 scope.

Should illustrate, the refractive index of above-mentioned (B) composition refers to the refractive index of utilizing irradiation to be cured previous (B) composition.

And refractive index for example can be measured according to JIS K0062.

In addition, preferably making the refractive index of above-mentioned (A) composition and (B) specific refractivity of composition is more than 0.01 value.

Its reason be due to, by making above-mentioned specific refractivity for the value in the scope of regulation, thereby can access the better incident angle dependence that has in optical transmission and diffusion and the optical diffusion film in wider light diffusion incident angle region.

That is, if above-mentioned specific refractivity is to be less than 0.01 value, incident light becomes narrow in the angle domain of shutter inner total reflection, so there is the opening angle of time diffusion to become excessively narrow.On the other hand, if above-mentioned specific refractivity is excessive large value, the intermiscibility of (A) composition and (B) composition variation too, likely cannot form shutter.

Therefore, more preferably make the value in the refractive index of (A) composition and scope that (B) specific refractivity of composition is 0.05～0.5, more preferably the value in 0.1～0.2 scope.

Should illustrate, herein so-called (A) composition and (B) refractive index of composition refer to and utilize (A) composition before being cured of irradiation and (B) refractive index of composition.

(v) content

In addition, preferably making optical diffusion film is the value in the scope of 10～80 % by weight by total amount 100 % by weight of composition with respect to optical diffusion film with the content of (B) composition in composition.

Its reason be due to, if (B) content of composition is the value that is less than 10 % by weight, (B) composition tails off with respect to the ratio that exists of (A) composition, from the width of the plate like region of (B) composition, compare excessively and diminish with the width of plate like region from (A) composition, be sometimes difficult to obtain having the dependent shutter of good incident angle.In addition, the length of the window shutter on the thickness direction of optical diffusion film becomes insufficient sometimes.On the other hand, if (B) content of composition is for surpassing the value of 80 % by weight, (B) composition becomes many with respect to the ratio that exists of (A) composition, from the width of the plate like region of (B) composition and the width of plate like region from (A) composition, compare excessive change large, be sometimes difficult on the contrary obtain having the dependent shutter of good incident angle.In addition, the length of the window shutter on the thickness direction of optical diffusion film becomes insufficient sometimes.

Therefore, the content that more preferably makes (B) composition is the value in the scope of 20～70 % by weight, the more preferably value in the scope of 30～60 % by weight by total amount 100 % by weight of composition with respect to optical diffusion film.

(1)-3 Photoepolymerizationinitiater initiaters

In addition, optical diffusion film in the present invention, with in composition, according to required, preferably contains Photoepolymerizationinitiater initiater as (C) composition.

Its reason be due to, by containing Photoepolymerizationinitiater initiater, thereby when optical diffusion film is irradiated to active energy ray with composition, can form efficiently shutter.

Herein, Photoepolymerizationinitiater initiater refers to the compound that produces free radical kind by the irradiation of ultraviolet isoreactivity energy line.

As above-mentioned Photoepolymerizationinitiater initiater, for example, can enumerate benzoin, benzoin methylether, benzoin ethyl ether, benzoin iso-propylether, benzoin n-butylether, benzoin isobutyl ether, acetophenone, dimethylamino acetophenone, 2,2-dimethoxy-2-phenyl acetophenone, 2,2-diethoxy-2-phenyl acetophenone, 2-hydroxy-2-methyl-1-phenyl-propane-1-ketone, 1-hydroxycyclohexylphenylketone, 2-methyl isophthalic acid-and 4-(methyl mercapto) phenyl ］-2-morpholinyl-propane-1-ketone, 4-(2-hydroxyl-oxethyl) phenyl-2-(hydroxyl-2-propyl group) ketone, benzophenone, to phenyl benzophenone, 4,4-diethylamino benzophenone, dichloro benzophenone, 2-methylanthraquinone, 2-EAQ, 2-tert-butyl group anthraquinone, 2-amino anthraquinones, 2-methyl thioxanthones, 2-ethyl thioxanthones, CTX, 2,4-dimethyl thioxanthones, 2,4-diethyl thioxanthone, benzil dimethyl ketal, acetophenone dimethyl ketal, to dimethylamine benzoic ether, few 2-hydroxy-2-methyl-1-4-(1-methyl ethylene) and phenyl ］ propane ］ etc., can use separately wherein a kind, also can combine two or more use.

Should illustrate, content when containing Photoepolymerizationinitiater initiater, preferably with respect to (A) composition and (B) total metering 100 weight portions of composition be the value in the scope of 0.2～20 weight portion, the more preferably value in the scope of 0.5～15 weight portion, the more preferably value in the scope of 1～10 weight portion.

(1)-4 other adjuvants

In addition, in not damaging the scope of effect of the present invention, can suitably add above-claimed cpd adjuvant in addition.

As such adjuvant, such as enumerating antioxidant, ultraviolet light absorber, antistatic agent, polymerization accelerant, polymerization inhibitor, infrared absorbent, plastifier, diluting solvent and levelling agent etc.

Should illustrate, the content of adjuvant like this, conventionally preferably with respect to (A) composition and (B) total metering 100 weight portions of composition be the value in the scope of 0.01～5 weight portion, the more preferably value in the scope of 0.02～3 weight portion, the more preferably value in the scope of 0.05～2 weight portion.

(2) operation (b): the 1st painting process

As shown in Fig. 9 (a), operation (b) is the optical diffusion film composition that 2 coatings are prepared for technique sheet material, forms the operation of the 1st coating layer 1a.

As technique sheet material, can use any in plastic foil, paper.

Wherein, as plastic foil, can enumerate the polyester mesenterys such as polyethylene terephthalate film, the polyolefin mesenterys such as polyethylene film, polypropylene screen, the cellulose mesenterys such as tri acetyl cellulose membrane, and polyimide mesentery etc.

In addition, as paper, such as enumerating viscose paper, coated paper and laminated paper etc.

In addition, if consider operation described later, preferably to the plastic foil of the excellent in dimensional stability of heat, active energy ray as technique sheet material 2.

As such plastic foil, in above-mentioned plastic foil, can preferably enumerate polyester mesentery, polyolefin mesentery and polyimide mesentery.

In addition, for technique sheet material, for after carrying out photocuring, resulting optical diffusion film is easily peeled off from technique sheet material, preferably the optical diffusion film in technique sheet material arranges peel ply by the coated face side of composition.

Above-mentioned peel ply can be used the known remover formation in the past such as silicon-type remover, fluorine series stripping agent, alkyd series stripping agent, ethylene series remover.

Should illustrate, the thickness of technique sheet material is preferably the value in the scope of 25～200 μ m conventionally.

In addition, as be coated with the method for composition for optical diffusion film on technique sheet material, such as can utilize scraper for coating method, rolling method, excellent painting method, scraper plate rubbing method, mould be coated with method and intaglio plate rubbing method etc. in the past known method carry out.

In addition, preferably making the thickness of the 1st coating layer is the value in the scope of 80～700 μ m.

Its reason be due to, by making the thickness of the 1st coating layer, be the value in above-mentioned scope, thereby can further form efficiently the 1st shutter.

That is, if the thickness of the 1st coating layer is the value that is less than 80 μ m, the curtailment of the 1st shutter forming, the incident light of keeping straight in the 1st shutter increases, and is sometimes difficult to obtain the homogeneity of the diffusion light intensity in light diffusion angular regions.On the other hand, if the thickness of the 1st coating layer is for surpassing the value of 700 μ m, while the 1st coating layer irradiation active energy ray being formed to the 1st shutter, the shutter forming due to the initial stage causes photopolymerisable direct of travel to spread, and is sometimes difficult to form desirable shutter.

Therefore, the thickness that more preferably makes the 1st coating layer is the value in the scope of 100～500 μ m, the more preferably value in the scope of 120～300 μ m.

(3) operation (c): the 1st active energy ray irradiation process

As shown in Figure 9 (b), operation (c) is to the 1st coating layer 1a, Yi Bian the 1st coating layer 1a is moved along moving direction E, Yi Bian use linear light source 125a to carry out the 1st active energy ray, irradiates 150a, forms the operation of the 1st shutter 13a.

More specifically, for example, as shown in Figure 10 (a) shows, by to the ultraviolet lamp 120(that is provided with the cold mirror 122 that optically focused uses in the UV-lamp 125a of wire for example, if commercially available product, WeiEYE GRAPHICS Co., Ltd. system, ECS-4011GX etc.) configuration heat radiation cut-off filter 121 and shadow shield 123(123a, 123b in), thereby take out the active energy ray 150a only being formed by the controlled direct light of irradiating angle, and the 1st coating layer 1a forming on technique sheet material 2 is irradiated.

In addition, as shown in Figure 11 (a) shows, while preferably seeing from film top, the value in the scope that the acute angle theta 2 that the long axis direction of linear light source 125a when the 1st active energy ray is irradiated becomes with the imaginary line E ' (length direction of film) of the moving direction E along the 1st coating layer 1a ' be is 10～80 °.

Its reason be due to, by the arrangement angles of such regulation linear light source, thereby combine with the arrangement angles of linear light source in aftermentioned operation (e), can manufacture more expeditiously by making incident light not only to the direction along its length direction, also carry out light diffusion and effectively expanded the strip optical diffusion film of the diffusion area of incident light to the direction with its length direction quadrature.

; if above-mentioned θ 2 ' is for being less than the value of 10 °; although also depend on the arrangement angles of the linear light source in aftermentioned operation (e), the light diffusion property to the direction diffusion of the length direction along film excessively reduces conventionally, and the diffusion area of incident light excessively diminishes sometimes.On the other hand, if above-mentioned θ 2 ' is for surpassing the value of 80 °, although also depend on the arrangement angles of the linear light source in aftermentioned operation (e), the light diffusion property to the direction diffusion of the length direction quadrature with film excessively reduces conventionally, and the diffusion area of incident light excessively diminishes sometimes.

Therefore, while more preferably seeing from film top, value in the scope that the acute angle theta 2 that the long axis direction of linear light source when the 1st active energy ray is irradiated becomes with the imaginary line of the moving direction along the 1st coating layer ' be is 35～55 °, the value in the scope of 40～50 ° more preferably, is further preferably the value in the scope of 44～46 °.

Should illustrate, linear light source 125a and coating layer 1a interval are preferably all roughly the same at an arbitrary position.

In addition, as the irradiating angle of active energy ray, as shown in Figure 10 (b), the irradiating angle θ 6 while conventionally preferably making the angle of the normal to a surface with respect to the 1st coating layer 1a be made as 0 ° is the value in the scope of-80～80 °.

Its reason be due to, if above-mentioned irradiating angle is the extraneous value of-80～80 °, the impact in the reflection on the 1st coating layer 1a surface etc. becomes large, is sometimes difficult to form sufficient shutter.

In addition, irradiating angle θ 6 preferably has width (irradiating angle width) θ 6 ' of 1～80 °.

Its reason be due to, if above-mentioned irradiating angle width θ 6 ' is for to be less than the value of 1 °, must make the translational speed of coating layer excessively reduce, sometimes manufacture Efficiency Decreasing.On the other hand, if above-mentioned irradiating angle width θ 6 ' is for surpassing the value of 80 °, irradiating light too disperses, and is sometimes difficult to form shutter.

Therefore, the irradiating angle width θ 6 ' that more preferably makes irradiating angle θ 6 is the value in the scope of 2～45 °, the more preferably value in the scope of 5～20 °.

Should illustrate to there is the angle of position, irradiating angle width θ 6 ' Shi，Jiang Qi middle as irradiating angle θ 6.

In addition, preferred Jie carries out the 1st active energy ray by the shadow shield with long groove shape active energy ray transmissive portions to be irradiated, and the long side direction of active energy ray transmissive portions is preferably the direction parallel with the long side direction of linear light source.

Should illustrate, as long as active energy ray transmissive portions is the state of transmission active energy ray, no matter which kind of mode all can.

For example, can consist of quartz glass, can be also simple space not existing light screening material etc.

Particularly, as shown in figure 12, being preferably situated between by by 2 shadow shield 123(123a, 123b) carry out in the long groove shape gap (active energy ray transmissive portions) that forms, and the long side direction in long groove shape gap is the direction parallel with the long axis direction of linear light source 125a.

By such configuration shadow shield, thereby the irradiating angle θ 6 by the active energy ray 150a shown in Figure 10 (a) can be adjusted to the value in the scope of regulation, effectively suppress that each surperficial position due to the 1st coating layer 1a is different to cause from the active energy ray 150a of linear light source 125a with excessive different angular illumination.

Its result, the pitch angle of the plate like region in the shutter that can make to form is even, and then makes the light diffusion property of resulting strip optical diffusion film even.

The surperficial peak illumination of the 1st coating layer while in addition, preferably making the 1st active energy ray irradiate is 0.1～50mW/cm ²scope in value.

Its reason be due to, the peak illumination when the 1st active energy ray is irradiated is the value in above-mentioned scope, thereby can form more efficiently the 1st shutter.

That is, if above-mentioned peak illumination is for being less than 0.1mW/cm ²value, be sometimes difficult to form clearly the 1st shutter.On the other hand, if above-mentioned peak illumination is for surpassing 50mW/cm ²value, infer curing rate and become too fast, be sometimes difficult to form clearly the 1st shutter.

The surperficial peak illumination of the 1st coating layer while therefore, more preferably making the 1st active energy ray irradiate is 0.3～10mW/cm ²scope in value, 0.5～5mW/cm more preferably ²scope in value.

Should illustrate, so-called peak illumination refers to the measured value that shows peaked part at the active energy ray that is irradiated to the 1st painting layer surface herein.

The surperficial accumulative total light quantity of the 1st coating layer while in addition, preferably making the 1st active energy ray irradiate is 5～300mJ/cm ²scope in value.

Its reason be due to, the accumulative total light quantity when the 1st active energy ray is irradiated is the value in above-mentioned scope, thereby can form more efficiently the 1st shutter.

That is, if above-mentioned accumulative total light quantity is for being less than 5mJ/cm ²value, be sometimes difficult to make the 1st shutter from top, be elongated to fully below.On the other hand, if above-mentioned accumulative total light quantity is for surpassing 300mJ/cm ²value, it is painted that the optical diffusion film sometimes obtaining produces.

The surperficial accumulative total light quantity of the 1st coating layer while therefore, more preferably making the 1st active energy ray irradiate is 10～200mJ/cm ²scope in value, 20～150mJ/cm more preferably ²scope in value.

In addition, preferably making the translational speed of the 1st coating layer is the value in the scope of 0.1～10m/ minute.

Its reason be due to, by making the translational speed of the 1st coating layer, be the value in above-mentioned scope, thereby can further form efficiently the 1st shutter.

That is,, if the translational speed of the 1st coating layer is to be less than the value of 0.1m/ minute, throughput rate excessively reduces sometimes.On the other hand, if the translational speed of the 1st coating layer is for surpassing the value of 10m/ minute, than the quick solidifying of the 1st coating layer, in other words, formation than the 1st shutter is fast, and active energy ray changes to the incident angle of the 1st coating layer, and the formation of the 1st shutter is insufficient sometimes.

Therefore, the translational speed that more preferably makes the 1st coating layer is the value in the scope of 0.2～5m/ minute, the more preferably value in the scope of 0.5～3m/ minute.

In addition, preferably with lamination, there is the state of active energy ray transmission sheet to irradiate active energy ray to the upper surface of the 1st coating layer.

Its reason be due to, by lamination active energy ray transmission sheet, thereby can effectively suppress the impact that oxygen hinders, form more efficiently the 1st shutter.

That is, by the upper surface lamination active energy ray transmission sheet to the 1st coating layer, thereby Yi Bian can stably prevent that the upper surface of the 1st coating layer from contacting with oxygen, Yi Bian make this sheet transmission, efficiently the 1st coating layer is irradiated to active energy ray.

Should illustrate, as active energy ray transmission sheet, so long as technique sheet material that can transmission active energy ray in the technique sheet material of recording in operation (b) (painting process) just can be used without particular limitation.

In addition, also preferably to become the mode of the fully curing accumulative total light quantity of the 1st coating layer, irradiate differently with the 1st active energy ray as operation (c), further irradiate active energy ray.

Owing to making the fully curing object of the 1st coating layer, so active energy ray now is not preferably used directional light, and use random light in any direct of travel.

(4) operation (d): the 2nd painting process

As shown in Figure 9 (c), operation (d) is for the 1st coating layer 1a ' coating optical diffusion film composition that is formed with the 1st shutter 13a, forms the operation of the duplexer 1c consisting of the 1st coating layer 1a ' and the 2nd coating layer 1b.

Should illustrate, while forming the 1st shutter 13a, in the situation that using active energy ray transmission sheet, this sheet be peeled off, the surface of coating layer 1a ' is exposed, then carry out aforesaid operations.

In addition, the optical diffusion film using in the formation of the 2nd coating layer 1b is preferably the identical optical diffusion film composition of composition for optical diffusion film using in the formation with the 1st coating layer 1a with composition.

Its reason be due to, by using identical optical diffusion film composition, thereby can be suppressed at the reflection at coating layer 1a ' and coating layer 1b′ interface, and can improve cohesive.

In addition, as being formed with the method that is coated with optical diffusion film use composition on the 1st coating layer of the 1st shutter, for example, can utilize scraper for coating method, rolling method, excellent painting method, scraper plate rubbing method, mould to be coated with the methods identical with above-mentioned operation (b) such as method and intaglio plate rubbing method carries out.

In addition, preferably making the thickness of the 2nd coating layer is the value in the scope of 80～700 μ m.

Its reason be due to, by making the thickness of the 2nd coating layer, be the value in above-mentioned scope, thereby can further form efficiently the 2nd shutter.

That is, if the thickness of the 2nd coating layer is the value that is less than 80 μ m, the curtailment of the 2nd shutter forming, the incident light of keeping straight in the 2nd shutter increases, and is sometimes difficult to obtain the homogeneity of the diffusion light intensity in light diffusion angular regions.On the other hand, if the thickness of the 2nd coating layer is for surpassing the value of 700 μ m, while the 2nd coating layer irradiation active energy ray being formed to the 2nd shutter, the shutter forming due to the initial stage causes photopolymerisable direct of travel to spread, and is sometimes difficult to form desirable shutter.

Therefore, the thickness that more preferably makes the 2nd coating layer is the value in the scope of 100～500 μ m, the more preferably value in the scope of 120～300 μ m.

(5) operation (e): the 2nd active energy ray irradiation process

As shown in Fig. 9 (d), operation (e) is to the 2nd coating layer 1b, make on one side to be moved with the duplexer 1c that the 2nd coating layer 1b forms by the 1st coating layer 1a ' that is formed with the 1st shutter 13a, using linear light source 125b to carry out the 2nd active energy ray on one side irradiates, form the 2nd shutter 13b, wherein, as shown in Figure 11 (b), while seeing from film top, the operation of the value in the scope that the acute angle theta 1 that the long axis direction of the linear light source 125b of the long axis direction of linear light source 125a when the 1st active energy ray is irradiated during with the 2nd active energy ray irradiation becomes ' be is 10～90 °.

; in having used 2 active energy ray irradiation process of linear light source; by stipulating the relation of the arrangement angles of each linear light source, thereby can efficiency manufacture well the strip optical diffusion film that the bearing of trend of the plate like region in the 1st shutter and the bearing of trend of the plate like region in the 2nd shutter are formed with the angular cross of stipulating.

Therefore, can manufacture by making incident light not only to the direction along its length direction, also carry out light diffusion and effectively expanded the strip optical diffusion film of the diffusion area of incident light to the direction with its length direction quadrature.

More specifically, can be in the situation that unlike the past a plurality of optical diffusion films being engaged, obtain making incident light at the direction along its length direction and the strip optical diffusion film that carries out light diffusion with the direction of its length direction quadrature.

That is, if by shown in Figure 11 (b) acute angle theta 1 ' for to be less than the value of 10 °, the diffusion area of incident light excessively diminishes sometimes.

Therefore, while more preferably seeing from film top, value in the scope that the acute angle theta 1 that the long axis direction of the linear light source of the long axis direction of linear light source when the 1st active energy ray is irradiated during with the 2nd active energy ray irradiation becomes ' be is 80～90 °, the value in the scope of 85～90 ° more preferably, is further preferably the value in the scope of 89～90 °.

In addition, as shown in Figure 11 (b), while preferably seeing from film top, the value in the scope that the acute angle theta 3 that the imaginary line E ' of the moving direction E of the duplexer 1c that the long axis direction of linear light source 125b when the 2nd active energy ray is irradiated forms with the 2nd coating layer 1b with the 1st coating layer 1a ' along by being formed with the 1st shutter 13a becomes ' be is 10～80 °.

Its reason be due to, by the arrangement angles of such regulation linear light source, thereby combine with the arrangement angles of linear light source in above-mentioned operation (c), more efficiency is manufactured well by making incident light not only to the direction along its length direction, also carry out light diffusion and effectively expanded the strip optical diffusion film of the diffusion area of incident light to the direction with its length direction quadrature.

; if above-mentioned θ 3 ' is for being less than the value of 10 °; although also depend on the arrangement angles of the linear light source in above-mentioned operation (c), the light diffusion property to the direction diffusion of the length direction along film excessively reduces conventionally, and the diffusion area of incident light excessively diminishes sometimes.On the other hand, if above-mentioned θ 3 ' is for surpassing the value of 80 °, although also depend on the arrangement angles of the linear light source in above-mentioned operation (c), the light diffusion property to the direction diffusion of the length direction quadrature with film excessively reduces conventionally, and the diffusion area of incident light excessively diminishes sometimes.

Therefore, while more preferably seeing from film top, the imaginary line angulation θ 3 ' of the long axis direction of linear light source when the 2nd active energy ray is irradiated and the moving direction along the duplexer consisting of the 1st coating layer and the 2nd coating layer is the value in the scope of 35～55 °, the value in the scope of 40～50 ° more preferably, is further preferably the value in the scope of 44～46 °.

Should illustrate, linear light source 125b and coating layer 1b interval are preferably all roughly the same at an arbitrary position.

In addition, for irradiating angle and the irradiating angle width of active energy ray, be preferably and use the numerical range that Figure 10 (a)～(b) situation of the 1st active energy ray irradiation of explanation is identical.

In addition, as shown in Figure 11 (b), while seeing from film top, the long axis direction of linear light source 125b when the long axis direction of linear light source 125a when the 1st active energy ray irradiates irradiates with the 2nd active energy ray, preferably the imaginary line E ' ' with respect to the moving direction E quadrature of the duplexer with consisting of the 1st coating layer 1a ' and the 2nd coating layer 1b becomes line symmetry.

Its reason is due to, the linear light source while irradiating by such configuration the 2nd active energy ray, thereby can make incident light in the optical diffusion film obtaining, and carries out more equably light diffusion.

Particularly, when being=45 ° of=45 ° of θ 2 ', θ 3 ', or while being respectively near its value, by configuring linear light source to become the mode of line symmetry, thereby the expansion on the expansion on the left and right directions of diffusion light and above-below direction can be expanded respectively to greatest extent.

Therefore, when above-mentioned optical diffusion film is applied to screen, can be by horizontal field angle and field angle expansion to greatest extent respectively longitudinally.

In addition, as shown in figure 12, for the 2nd active energy ray, irradiate, the reason identical according to the situation of irradiating with the 1st active energy ray, also be preferably situated between and undertaken by the long groove shape gap being formed by 2 shadow shields, and the long side direction in long groove shape gap is preferably the direction parallel with the long axis direction of linear light source.

The surperficial peak illumination of the 2nd coating layer while in addition, preferably making the 2nd active energy ray irradiate is 0.1～50mW/cm ²scope in value.

Its reason be due to, the peak illumination when the 2nd active energy ray is irradiated is the value in above-mentioned scope, thereby can form more efficiently the 2nd shutter.

That is, if above-mentioned peak illumination is for being less than 0.1mW/cm ²value, be sometimes difficult to form clearly the 2nd shutter.On the other hand, if above-mentioned peak illumination is for surpassing 50mW/cm ²value, infer curing rate and become too fast, sometimes cannot form clearly the 2nd shutter.

The surperficial peak illumination of the 2nd coating layer while therefore, more preferably making the 2nd active energy ray irradiate is 0.3～10mW/cm ²scope in value, 0.5～5mW/cm more preferably ²scope in value.

The surperficial accumulative total light quantity of the 2nd coating layer while in addition, preferably making the 2nd active energy ray irradiate is 5～300mJ/cm ²scope in value.

Its reason be due to, the accumulative total light quantity when the 2nd active energy ray is irradiated is the value in above-mentioned scope, thereby can form more efficiently the 2nd shutter.

That is, if above-mentioned accumulative total light quantity is for being less than 5mJ/cm ²value, be sometimes difficult to make the 2nd shutter to extend fully from top downwards.On the other hand, if above-mentioned accumulative total light quantity is for surpassing 300mJ/cm ²value, it is painted that the optical diffusion film sometimes obtaining produces.

The surperficial accumulative total light quantity of the 2nd coating layer while therefore, more preferably making the 2nd active energy ray irradiate is 10～200mJ/cm ²scope in value, 20～150mJ/cm more preferably ²scope in value.

In addition, in the 2nd active energy ray irradiates, the reason identical according to the situation of irradiating with the 1st active energy ray, also preferably making by being formed with the 1st coating layer of the 1st shutter and the translational speed of the duplexer that the 2nd coating layer forms is the value in the scope of 0.1～10m/ minute, the more preferably value in the scope of 0.2～5m/ minute, the more preferably value in the scope of 0.5～3m/ minute.

In addition, from the identical viewpoint of the situation with operation (c), also preferably with lamination, there is the state of active energy ray transmission sheet to irradiate active energy ray to the upper surface of the 2nd coating layer.

In addition, also preferably to become the mode of the fully curing accumulative total light quantity of the 2nd coating layer, irradiate differently with the 2nd active energy ray as operation (e), further irradiate active energy ray.

Owing to making the fully curing object of the 2nd coating layer, so active energy ray now is not preferably used directional light, and use random light on any direct of travel.

Should illustrate, above-mentioned operation (d)～(e) can be used a conveyor and operation (b)～(c) carry out continuously, also the 1st coating layer that is formed with the 1st shutter by operation (b)～(c) obtain can be reclaimed with roller shape, and be positioned over other conveyor and carry out operation (d)～(e).

Therefore, for the former, the linear light source in the linear light source in operation (c) and operation (e) is separately set, for the latter, same linear light source change (rotation) arrangement angles can be used.

Embodiment

Below, with reference to embodiment, further the manufacture method of optical diffusion film of the present invention is elaborated.

［ embodiment 1 ］

1. low-refraction polymerizable compound (B) composition is synthetic

In container, accommodate as 1 mole of the polypropylene glycol (PPG) of the weight-average molecular weight 9200 of (B2) composition, and with respect to this, accommodate as 2 moles of the isophorone diisocyanate (IPDI) of (B1) composition with as after 2 moles of the 2-hydroxyethyl methacrylates (HEMA) of (B3) composition, carry out according to conventional methods polymerization, obtain the polyethers urethane methacrylate of weight-average molecular weight 9900.

Should illustrate, the weight-average molecular weight of polypropylene glycol and polyethers urethane methacrylate is the polystyrene conversion value determining according to following condition with gel permeation chromatography (GPC).

GPC determinator: TOSOH Co., Ltd. system, HLC-8020

GPC column:TOSOH Co., Ltd. system (following, by recording by order)

TSK?guard?column?HXL-H

TSK?gel?GMHXL（×2）

TSK?gel?G2000HXL

Measure solvent: tetrahydrofuran

Measure temperature: 40 ℃

2. the preparation of composition for optical diffusion film

Then, polyethers urethane methacrylate 100 weight portions with respect to the weight-average molecular weight 9900 of resulting conduct (B) composition, add the adjacent phenyl phenoxy group of acrylic acid ethoxy ethyl ester (the Xin Zhong village KCC system as the weight-average molecular weight 268 being represented by following formula (3) of (A) composition, NK ESTER A-LEN-10) after 100 weight portions and conduct 2-hydroxy-2-methyl propiophenone 5 weight portions of (C) composition, under the condition of 80 ℃, heat mixing, obtain the optical diffusion film composition that the 1st shutter formation use and the 2nd shutter form use.

Should illustrate, (A) composition and (B) refractive index of composition use Abbe refractometer (ATAGO Co., Ltd. system, Abbe refractometer DR-M2, Na light source, wavelength 589nm) to measure according to JIS K0062, result is respectively 1.58 and 1.46.

3. the 1st painting process

Then, the membranaceous transparent polyethylene terephthalate film as technique sheet material (following, to be called PET) is coated with to resulting optical diffusion film composition, forms the 1st coating layer of thickness 165 μ m.

4. the 1st active energy ray irradiation process

Then, prepare the ultraviolet lamp that subsidiary optically focused forms with cold mirror in wire high-pressure sodium lamp as shown in Figure 10 (a) shows (EYE GRAPHICS Co., Ltd. system, ECS-4011GX).

Now, while seeing from film top, the mode that becomes 45 ° with the long axis direction of linear light source and the acute angle theta that imaginary line was become 2 of moving direction along the 1st coating layer arranges ultraviolet lamp.

Then, on heat radiation cut-off filter frame, shadow shield is set, the illuminated surperficial ultraviolet ray in the 1st coating layer is set as: when the normal of the 1st painting layer surface when seeing from the long axis direction of linear light source is made as 0 °, from the ultraviolet irradiation angle (θ 6 of Figure 10 (b)) of linear light source direct projection, become 16 °.

In addition, be set as: the height from the 1st painting layer surface to linear light source is that 2000mm, peak illumination are 1.26mW/cm ², accumulative total light quantity become 23.48mJ/cm ².

In addition, in order to prevent that the reflected light of shadow shield etc. from becoming parasitic light and the photocuring of the 1st coating layer is exerted an influence in irradiating machine inside, as shown in figure 12,2 shadow shields are also set near conveyor, so that the 1st coating layer is only irradiated to the ultraviolet mode of directly sending from linear light source, set.

More specifically, as shown in figure 12, to form the long groove shape gap that formed by 2 shadow shields (gap width: mode 35cm) configures, and arranging in the mode that the long side direction in this long groove shape gap becomes the direction parallel with the long axis direction of linear light source.

Then, the speed with 1.0m/ minute moves to the right in Fig. 9 (b) to utilize on one side conveyor to make the 1st coating layer, irradiation ultraviolet radiation on one side, the length that obtains length on length direction (moving direction of the 1st coating layer) and be on 30m, Width is the 1st coating layer that is formed with the 1st shutter of the strip of 1.4m, thickness 165 μ m.

Then, in order to realize reliably, solidify, at the stripping film with ultraviolet (uv) transmission that exposes face side laminate thickness 38 μ m (Lintec Co., Ltd. system, the SP-PET382050 of the 1st coating layer; The transmissivity 84.3% of the surperficial center line average roughness 0.01 μ m of ultraviolet ray irradiation side, haze value 1.80%, image definition 425, wavelength 360nm) as active energy ray transmittance sheet.

Then, to become peak illumination 13.7mW/cm ², accumulative total light quantity 213.6mJ/cm ²mode carry out scattered light irradiation.

Should illustrate, above-mentioned peak illumination and accumulative total light quantity are by will UV METER(EYE GRAPHICS Co., Ltd. system of light-receiving device being installed, EYE ultraviolet ray accumulative total illuminometer UVPF-A1) be arranged on that the position of the 1st coating layer measures.

In addition, the thickness of the 1st coating layer that is formed with the 1st shutter of resulting strip is to use level pressure thickness tester (precious Co., Ltd. of institute system, the TECLOCK PG-02J of making) to measure.

5. the 2nd painting process

Then, active energy ray transmission sheet is peeled off from the 1st coating layer that is formed with the 1st shutter of resulting strip.

Then, the face that exposes of the 1st coating layer that is formed with the 1st shutter of resulting strip is coated on to the optical diffusion film composition obtaining in above-mentioned operation, forms the 2nd coating layer of thickness 165 μ m.

6. the 2nd active energy ray irradiation process

Then, while seeing from film top, the acute angle theta that long axis direction was become 1 of the linear light source of the long axis direction of the linear light source while irradiating with the 1st active energy ray during with the 2nd active energy ray irradiation becomes the mode of 90 ° ultraviolet lamp is set, in addition, with the 1st active energy ray irradiation process similarly, irradiation ultraviolet radiation, obtains the strip optical diffusion film that inside has the thickness 330 μ m of the 1st shutter and the 2nd shutter.

Should illustrate, while seeing from film top, the acute angle theta 3 that the imaginary line of the moving direction of the duplexer that the long axis direction of linear light source forms with the 2nd coating layer with the 1st coating layer along by being formed with the 1st shutter becomes is 45 °.

In addition, after the 2nd coating layer irradiation ultraviolet radiation, also with the situation of the 1st coating layer similarly, with lamination, have the state of active energy ray transmission sheet (stripping film with ultraviolet (uv) transmission), irradiate scattered light, realize reliably and solidifying.

In addition, for the optical diffusion film obtaining, as shown in figure 13, while having confirmed to see from film top, the bearing of trend of the plate like region in the 1st shutter is 90 ° with the acute angle that the bearing of trend of plate like region in the 2nd shutter becomes.

In addition, while having confirmed to see from film top, the acute angle that the bearing of trend of plate like region in the 1st shutter and the length direction of film become is 45 °.

And then while having confirmed to see from film top, the acute angle that the bearing of trend of plate like region in the 2nd shutter and the length direction of film become is 45 °.

In addition, shown in Figure 14 (a), along the face with the length direction quadrature of film, cutting off the photo in the cross section that resulting optical diffusion film forms, the length direction along with film is parallel and cut off the photo in the cross section that resulting optical diffusion film forms with the face of face quadrature shown in Figure 14 (b).

Should illustrate, the cut-out of optical diffusion film is carried out with razor, and the optical microscope for shooting (reflective observing) of the photo in cross section carries out.

7. measure

As shown in figure 13, from the downside (the 1st shutter place side) of resulting optical diffusion film, to this film from the direction incident light with face quadrature.

Then (Suga Test Instruments Co., Ltd. system VC-2), obtains the spectrogram of the diffusion light in the direction with the length direction quadrature of film and in the direction parallel with the length direction of film, to use angle colour meter.

That is, as shown in Figure 15 (a) shows, obtain using the light diffusion angle of the diffusion light being spread by optical diffusion film (°) as transverse axis, the spectrogram using the relative intensity (-) of diffusion light during as the longitudinal axis.

Herein, the spectrogram A shown in Figure 15 (a) is corresponding to the diffusion light of the direction of the length direction quadrature with film, and spectrogram B is corresponding to the diffusion light of the parallel direction of the length direction with film.

In addition, use conoscope (autronic-MELCHERS GmbH company system), as shown in Figure 15 (b), the photo of the diffusion light while obtaining seeing from the Z direction of Figure 13.

Result shown in above-mentioned Figure 15 (a)～(b) is consistent with the light diffusion property of predicting according to the film with inner structure as shown in Figure 13.

［ reference example 1 ］

In reference example 1, in the 1st active energy ray irradiation process, while seeing from film top, making the length direction of linear light source is 90 ° with the acute angle theta 2 that the imaginary line of moving direction along the 1st coating layer becomes, in addition, similarly to Example 1, the 1st coating layer is carried out to the 1st active energy ray irradiation process, obtain the 1st coating layer (inside is formed with the coating layer of the 1st shutter).

For the 1st coating layer that is formed with the 1st shutter now obtaining, as shown in Figure 16 (a), while having confirmed to see from film top, the acute angle that the bearing of trend of the plate like region in shutter becomes with its length direction is 90 °.

Then, as shown in Figure 16 (b), resulting the 1st coating layer that is formed with the strip of the 1st shutter is cut off in the longitudinal direction every 1.1m, obtain being formed with the 1st coating layer of a plurality of non-strips of the 1st shutter.

Then,, as shown in Figure 16 (c), the 1st coating layer of a plurality of non-strips that are formed with the 1st shutter that obtain respectively planar after half-twist, is engaged respectively in mode transversely arranged and that be spaced apart below 0.5mm.

Thus, as shown in Figure 16 (c), while obtaining seeing from film top, the acute angle that the bearing of trend of the plate like region in shutter becomes with its length direction is the 1st coating layer (inside is formed with the coating layer of the 1st shutter) of the strip that is formed with the 1st shutter of 0 °.

Then, for by resulting the 1st coating layer that is formed with the strip of the 1st shutter shown in Figure 16 (c), coating layer by the strip shown in Figure 16 (a) is situated between and is undertaken stacked by the acrylic acid series transparent adhesive layer of thickness 25 μ m, the 2nd coating layer as being formed with the strip of the 2nd shutter, obtains optical diffusion film.

In addition, for the optical diffusion film obtaining, as shown in figure 17, while having confirmed to see from film top, the bearing of trend of the plate like region in the 1st shutter is 90 ° with the acute angle that the bearing of trend of plate like region in the 2nd shutter region becomes.

In addition, while having confirmed to see from film top, the acute angle that the bearing of trend of plate like region in the 1st shutter and the length direction of film become is 0 °.

And then while having confirmed to see from film top, the acute angle that the bearing of trend of plate like region in the 2nd shutter and the length direction of film become is 90 °.

In addition, at the photo that shown in Figure 18 (a), the face along with the length direction quadrature of film is cut off to the cross section that resulting optical diffusion film forms, the length direction along with film is parallel and cut off the photo in the cross section that resulting optical diffusion film forms with the face of face quadrature shown in Figure 18 (b).

In addition, similarly to Example 1, measure the downside by resulting optical diffusion film, for this film, the light spread condition during from direction incident light with face quadrature.

The spectrogram of the diffusion light obtaining not having jointed part incident light is shown in to Figure 19 (a), and the photo of the diffusion light when now the Z direction from Figure 17 is seen is shown in Figure 19 (b).

Result shown in above-mentioned Figure 19 (a)～(b) is consistent with the light diffusion property of predicting according to the film with inner structure as shown in figure 17.

But, when the part incident light of seam, confirmed as shown in Figure 20 (a)～(b) unfavorable condition that causes light diffusing easily to become inhomogeneous due to the seam portion of film.

［ comparative example 1 ］

In comparative example 1, do not implement the 2nd painting process and the 2nd active energy ray irradiation process, in addition, manufacture similarly to Example 1 optical diffusion film.

In addition, for the optical diffusion film obtaining, as shown in figure 21, while having confirmed to see from film top, the acute angle that the bearing of trend of the plate like region in shutter becomes with the length direction of film is 45 °.

In addition, at the photo that shown in Figure 22 (a), the face along with the length direction quadrature of film is cut off to the cross section that resulting optical diffusion film forms, the length direction along with film is parallel and cut off the photo in the cross section that resulting optical diffusion film forms with the face of face quadrature shown in Figure 22 (b).

The spectrogram of the diffusion light obtaining is shown in to Figure 23 (a), when the Z direction from Figure 21 is seen the photo of diffusion light be shown in Figure 23 (b).

Wherein, Figure 23 (a) is illustrated in along the spectrogram of the direction of the dispersal direction (long axis direction) of the diffusion light shown in Figure 23 (b).

Result shown in above-mentioned Figure 23 (a)～(b) is consistent with the light diffusion property of predicting according to the film with inner structure shown in Figure 21.

Utilizability in industry

As detailed above, according to the present invention, the manufacture method of stipulating by enforcement, thus can access the strip optical diffusion film that the bearing of trend of the plate like region in the 1st shutter and the bearing of trend of the plate like region in the 2nd shutter are formed with the angular cross of stipulating.

Its result, in strip optical diffusion film, by making incident light not only to the direction along its length direction, also carries out light diffusion to the direction with its length direction quadrature, thereby can effectively expand the diffusion area of incident light.

Therefore, optical diffusion film of the present invention is expected to contribute to significantly throughput rate, high-qualityization of the large-area optical diffusion film that projection screen, reflective liquid crystal device etc. are used especially.

Symbol description

1a: the 1st coating layer, 1a ': the 1st coating layer that is formed with the 1st shutter, 1b: the 2nd coating layer, 1c: the duplexer being formed by the 1st coating layer and the 2nd coating layer, 2: technique sheet material, 10: optical diffusion film, 12: the plate like region that refractive index is relatively high, 13: shutter, 13a: the 1st shutter, 13b: the 2nd shutter, 13 ': the boundary surface of shutter, 14: the plate like region that refractive index is relatively low, 20: utilize manufacture method of the present invention and the optical diffusion film that obtains, 50 ': the spread condition of light, 51 ': the spread condition of diffusion light, 120: ultraviolet lamp, 121: heat radiation cut-off filter, 123: shadow shield, 125: linear light source, 150: active energy ray.

Claims

1. an optical diffusion film, is characterized in that, is film thickness direction along film starts to have successively the strip of the 1st shutter and the 2nd shutter optical diffusion film from below,

Described the 1st shutter and the 2nd shutter be by refractive index respectively different a plurality of plate like region that a plurality of plate like region form and described refractive index is different at the shutter that alternately configured in parallel forms of the either direction along face, and,

While seeing from film top, the acute angle theta 1 that the bearing of trend of the described plate like region in described the 1st shutter is become with the bearing of trend of described plate like region in described the 2nd shutter is the value in the scope of 10～90 °.

2. optical diffusion film according to claim 1, it is characterized in that, while seeing from film top, the acute angle theta 2 that the bearing of trend of described plate like region in described the 1st shutter and the length direction of film are become is the value in the scope of 10～80 °, and, while seeing from film top, the acute angle theta 3 that the bearing of trend of plate like region in described the 2nd shutter and the length direction of film are become is the value in the scope of 10～80 °.

3. optical diffusion film according to claim 1, it is characterized in that, while seeing from film top, the bearing of trend of the described plate like region in the bearing of trend of the described plate like region in described the 1st shutter and described the 2nd shutter is that line is symmetrical with respect to the imaginary line of the length direction quadrature with film.

4. optical diffusion film according to claim 1, is characterized in that, the value in the scope that the length that makes the Width in described optical diffusion film is 0.1～3m, and to make the length of length direction be value more than 3m.

5. optical diffusion film according to claim 1, is characterized in that, is wound into roller shape and forms.

6. optical diffusion film according to claim 1, is characterized in that, makes the thickness of described the 1st shutter and the 2nd shutter be respectively the value in the scope of 50～500 μ m.

7. optical diffusion film according to claim 1, is characterized in that, makes the width of the described plate like region in described the 1st shutter and the 2nd shutter be respectively the value in the scope of 0.1～15 μ m.

8. optical diffusion film according to claim 1, is characterized in that, the starting material that make described optical diffusion film are the optical diffusion film composition that contains 2 kinds of polymerizable compounds that refractive index is different.